Tetra's Safestart Is An Aquarium Water Conditioner That Will Help Reduce Ammonia And Nitrite, Contains Live Bacteria To Promote Biological Filtration And Prevents New Tank Syndrome From Affecting To Fish In Your Tank. Safe Start Begins Working Immediately Which Allows You To Add Additional Fish Right Away. This Patented Mix Of Nitrosomonas, Nitrosospira And Nitrospira Is Proven To Work. Refrigeration Is Not Necessary Tetra Safestart: 100 Ml - 3.38 Oz #77961 - Aquarium Bio Additives